Engine-starter.



C. L. KENNEDY.

ENGINE STARTER.

APPLICATION mw swr. 25, 1912.

1,189,260. Patented July 4, 1916.

PTE-E# 14 f5 L Mor) L 4 la UNITED STATES PATENT OFFICE.

CARLTON L. KENNEDY, 0F SOUTH BRAINTREE, MASSACHUSETTS, ASSIGNOR TO THE HOLTZER-CABOT ELECTRIC COMPANY, OF BROOKLINE, MASSACHUSETTS, A CORPO- RATION 0F MASSACHUSETTS.

Application filed September 25, 1912.

0 all whom t may concern Be it known that I, CARLTON L. KENNEDY, a citizen of the United States, residing at South Braintree, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Engine-Starters; and I do hereby declare the following to he a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to engine starters, and more particularly to starters for internal combustion engines, such as automobileengines, in which a dynamo-electric machine is used as a dynamo to charge a storage battery and as a motor to start the engine.

The object of the invention is to produce a simple and efficient system of this type in which the dynamo-electric machine is selfregulated when running as a dynamo, and is arranged to give a large torque when it operates as a motor to start the engine. With this object in view, the present invention consists in the engine starter herein after described and particularly pointed out in the claims.

In the accompanying drawings, illustrating the preferred form of the invention, Figure 1 is a diagram of the system; and Fig. 2 a detail of construction.

The automobile engine E, the gearing G and the pump P are all as is common in automobiles, the pump shaft being directly geared with the crank shaft of the engine. Connected with the pump shaft is a dynamoelectric machine which is thereby directly connected with the engine and adapted to drive it for starting, or to be driven by it for generating current for the purpose of supplying the various current consuming devices on the machine, such as head lights H and H2, the side lamps L and L2, the dash lamp L3, tail lamp L4 and horn or other warning signal W, and also the ignition system I. The starting switch S is employed for making the necessary connections to operate the dynamo-electric machine D as a motor. The horn button w is provided in the horn circuit for use in operating the horn W.

Specification of Letters Patent.

ENGINE-STARTER.

Patented July 4, 1916.

Serial No. 722,201.

In the illustrated embodiment of the invention, the dynamo-electric machine B has both shunt and series field windings. The shunt winding is indicated at C. The series Winding is divided into two sections or coils indicated at C2 and C3, the section or coil C2 being of lower resistance than the section or coil C3. The dynamo-electric machine commutator is indicated at A and the cutout is indicated at O. The cut-out O is illustrated in detail in Fig. 2. The cut-out is a centrifugal switch and operates to close the circuit upon which it is located upon the attainment by the dynamo-electric machine of a predetermined critical speed. The particular cut-out shown forms no part of the present invention, but is one which has been found to give satisfaction in work of this kind. Three 120 degree collector ring segments l, 2 and 3 insulated from each other and from the dynamo-electric machine shaft are supported on the shaft 4, being keyed thereto. Brushes 14 and 140 bear upon the collector ring at diametrically opposite points, and consequently the insulation between the segments insulates the brushes from each other. The centrifugal switch member consists of two segmental heads 5 and 6 secured to the ends of a spring 7, in turn secured to the hub 8. The spring 7 holds the switch heads 5 and 6 contracted in the position shown in Fig. 2 until the critical speed is reached, at which time the heads 5 and 6 fly outwardly and make contact with the inside of the collector ring formed by the three segments 1, 2 and 3. The heads 5 and 6 are electrically connected by means of the spring 7 and when they fly outwardly, they electrically connect the two segments l and 3. The spring 7 is electricallv connected with the segment 2 by means of the contact spring 9 which bears against the inside of the segment 2 so that when the critical speed is reached, the collector ring becomes a continuous conductor, and the cut-out O completes the circuit in which it is located.

The connections between the parts of the apparatus will be described in connection with a description of the operation of the system in performing the various functions Which it discharges, Beginning with the automobile in a state of rest and the engine not running. Assuming that the storage battery is properly charged, the operator deciding to start the engine, closes the starting switch S. At this time the cut-out is open and the current from the end pole 10 of the battery runs ,through the wire 11 to the series field coil C2, thence through the wire 12 to the star-ting switch S, thence through the wire 13 to the cut-out brush 14, thence through the wire 15 to the conimutator brush connection 16, through the armature A to the commutator brush connection 17, thence through the wire 18 to the end pole 190 of the battery. The series field coil C2 is made of few turns of heavy wire. This is a circuit of low resistance which allows a very heavy current to flow through the dynamo-electric machine which acts as a compound wound motor and exerts a very heavy torqueA which is sufficient to start the engine even under unfavorable conditions.

While in the illustrated embodiment of the invention, the series eld windings are shown as arranged in two sections C2 and C3, and so connected that the current 'Hows through both sections in series when the dynamo-electric machine is driven as a dynamo in order to secure an efficient regulation of the dynamo, and through the section C2 only when the dynamo-electric machine is being run as a motor in order that a series field circuit of low resistance may `be provided to permit a large current to pass through the armature when the machine is run as a motor, it is obvious that other arrangements of the series field winding might be had to produce these results, and the invention is, therefore, not limited to the particular arrangement of series field winding and its connections shown in the drawings, but the series field winding may be otherwise arranged and connected within the scope of the claims.

The speed at which the dynamo-electric machine D runs as a motor is lower than the critical speed at which the heads 5 and 6 engage the collector ring of the cut-out C. Consequently, the cut-out O operates to cut out the other series field coil C3 when the dynamo electric machine D runs as a motor. The storage battery is a 12 volt battery and the entire current from' the battery is available for use in driving the motor. The starting switch should open as soon as the engine starts, and it acts to open as soon as pressure upon it is removed. As soon as the engine starts and increases in speed sufiiciently to bring the dynamo-electric machine armature up to the critical speed, the cut-out C operates to close the circuit which it has held open, and with the opening of the starting switch and the closing of the cut-out O, the dynamo-electric machine becomes a dynamo and operates to generate current for charging the storage battery.

The conditions for charging the storage battery are that the engine should be running at a speed sufficiently high to cause the cut-out C to close the circuit in which it is located, and thereupon the dynamo-electric machine D, acting as a dynamo, operates to charge the storage battery B. The current generated by the dynamo-electric machine is taken off' at one comniutator brush connection 16 and fiows through the wire 15 to the cut-out brush 14, thence through the eutout O, the cut-out brush 140` the wire 19,

through the series field coil Ctand the series j field coil C2, and thence through the wire 11 to the pole 10 of the storage battery. he other armature brush 17 is connected by the wire 18 with the other pole 190 of the storage battery. The series field coil C3 is made of a much larger number of turns of smaller wire than the series field coil C2. These coils are composed of enough windings or turns of wire so that the current can never reach a value which will damage the storage battery B.

The operation of the system for use in supplying current to the various current consuming devices of the machine, to wit, the head, side, tail and dash lights and the horn and the ignition system, is such that they are fed directly from the armature through the cut-out without passing through the series field coils. As a consequence of which, the current consumed for these devices has no material effect upon the charging current for the battery which is approximately constant irrespective of the amount of current used for such devices. The circuits for the various current consuming devices when the dynamo-electric machine is a dynamo are as follows. Starting with the commutator brush connection 1G, the connection is through the wire 15 to the cut-out O, to wire 20 which is a lead wire to one side of four of the current using devices. The connection is as follows:- through the wire 21, to the controlling switch 22, through the wire to thc right hand head light H2, thence through the wire 24 to the neutral wire 25; through the wire 26, switch 27, wire 28 to the side lamp L2, thence through the wire 29 to the neutral wire 25; through the wire 30. the switch 31, the wire 32 to the tail lamp L4, and thence through the wire 33 to the neutral wire 25; and through the wire 34 and button w when it is closed) and the wire to the horn YN which connects by the wire 36 with the neutral connection 25 of the right hand side lamp L2. F rom the other pole 17 of the armature connection is had through the wire 18 to the lead wire 37 and from this lead wire or generator main connection is had through the wire 38, the switch 39, the wire l0 to the left handhead light H', and thence through the wire 41 to the neutral wire 25; through the wire 42, the switch 43, the wire 44 to the left hand side lamp L', thence through the wire 45 to the neutral wire 25; through Vthe wire 46, switch 4:7, the wire v-ii to the dash lamp L3, and thence through the wire 49 to the neutral wire 25; and through the wire`50, switch 51,. wire 52 to the ignition system I, and thence through the wire 53 tothe neutral wire 25. In cases where the engine is running at low speed and a considerable amount of current is taken by the current consuming devices, the voltage drop due to' the passage of this current through the armature may be enough to cause its voltage to drop below that of the storage battery, and this brings us to aconsideration of the case where the current consuming devices are fed by the battery and the dynamo electric machine, operating as a dynamo, in cooperation with each other. For here part of the current will How lfrom the battery through the series coils, thus increasing the field magnetism of the dynamo and thereby increasing the voltage to a point where it will approximately equal that of the batter-y.

In case the current consuming devices (and in this case the ignition system is to be excluded) demand CurrentV when the engine is not running, the current will be drawn from the storage battery, partially .from one end andv partially from the other end thereof, the neutral wire l25 being connected to the middle terminal 250 of the storage battery, as shown, one half of the current operating devices drawing their currentv from one end of the storage battery, and the other half drawing from the other end ofthe storage battery. Under these circumstances, that is, when the current consuming devices demand current and the engine is not running, the cut-out is open and the wifes 15 and 18 are dead. Then the feeder 2O will draw its current through the wire 19, the series field coils C3 and C2, and the wire 11 from pole 10 of the battery and the devices drawing current from this feeder 20 will be connected with the neutral wire, and therefore with the middle terminal 250 of the storage battery. The feed wire 37 will draw its current from the opposite pole 190 of the storage battery, and the devices supplied with current by this feeder will, as above described, be connected through the neutral wire with the middle terminal of the battery. The left hand head light H', the left hand side lamp L, the ignition I and the dash lamp L3 are supplied with current by that half of the storage battery between the middle terminal 250 and the end pole 190, while the right hand head light H2, the right hand side lamp L2, the horn W and the tail lamp L* draw their current from that portion of the storage battery between the pole 10 and the middle terminal 250, four current consuming devices being connected with each half of the battery.

From motives of economy it is desirable to use the comparatively cheap lead plate storage battery. This form of battery is injured if it receives an excessive current or is over-charged with any considerable volume of current. The system of the present invention is so arranged that at no time will the battery B be charged with any considerable volume of current. If the conditions are such that there is a tendency for any considerable volume of current to flow into the battery B, this current will, by passing through the series coils C2 and C3, weaken the dynamo field and this automatically decreases the dynamo voltage, and consequently limits the current furnished to the battery. This effect is accentuated by the use of the high resistance field coil C3 which has a large number of windings. The large number of current turns in the fine Windings of the coil C3 has such a weakening effect upon the dynamo field that under no conditions is it possible to cause a current to flow through the series field C3 of a volume sufficient to damage the battery. Moreover, the resistance of the series field C3 acts as a ballast resistance to prevent too great a charging current from flowing into the battery. The system thus automatically prevents the battery from being damaged by an excessive charging current, and the cheaper lead storage battery maybe used instead of the more expensive nickel-iron storage battery which is not injured by such over-charging.

The illustrated embodiment of the present invention is intended for use in connection with automobile engines, but is equally adapted for use with motor-boat and other engines, and the claims are to be read and understood as comprehending such uses of the invention. The invention is not limited to the illustrated embodiment as it may be embodied in other forms within the scope of the following claims.

1. The combination of an engine, a storage battery, a current consuming device, a direct current dynamo-electric machine connected with the engine to draw current from the storage battery as a motor to start the engine and to be driven by the engine as a dynamo to furnish current to the current consuming device and for charging the storage battery, said dynamo-electric machine ries field winding and the battery, said series field winding being so wound that when the battery receives current the machine field is weakened and when the battery furnishes current the field is strengthened by the current in the circuit through the armature, series field winding and battery, a cutout. open when the machine is at rest and closed when the machine is running at full speed, and a connection containing a Start ing switch shunting the cut-out.

2. The combination of an engine, a storage battery, a current consumingdevicc, a direct current dynamo-electric machine connected with the engine to draw current frompthe storage battery as a motor to start the engine andi to be driven by the engine as a dynamo. to furnish current to the current consuming device and for charging the storage battery, said dynamo-electric machine having an armature, a shunt field winding connected across the armature and a series field winding, a circuit from the armature through the current consuming device, a circuit from the armature through the series field winding and the battery, an automatic cut-out in the circuit through the armature and battery closed when the dynamo-electric machine is running as a dynamo and open when the dynamo-electric machine is running as a .m0tor, and a con-v nection shunting thecut-out and containing a startingswitch to lead current aroundthe cut-out to operate the dynamo-electric machine as a motor to start the engine.

3. The combination of an engine, a storage battery, a current consuming device, a direct ycurrent dynamo-electric machine connected with the engine to draw current from the storage battery as a motor to start the engine and to be driven .by the engine as a dynamo to furnishy currentto the current consuming device and for charging the storage battery, said dynamo-electric machine having an armature, a shunt field Winding and a series field winding divided into two sections one of which is of higher resistance than the other, an automatic cutout closed when the machine is running as a dynamo and open when running as a motor, a connection through the armature and cutout to the current consuming device, a connection through the armature, cut-out and both sections of the-series field winding to the battery, said series field winding being wound so that the field is strengthened when current flows from the battery and weakened whenA current fiow's to the battery, and a shunt connection containing a starting switch around the cut-out and the higher resistancesection of the series field winding.

4. The combination of an engine, a storage battery, a current consuming device, a direct current dynamo-electric machine connected with the engine to draw current from the battery as amotor to start the engine and to be driven by the engine as a dynamo when the engine is running to furnish current to the current consuming device and for charging the storage battery, said dynamo-electric machine having an armature, a shunt field winding and a series field winding divided into two sections, one of which is of higher resistance than the other, a connection from the armature to the current consuming device, a connection from .the armature through both-sections of the series field winding to the battery, said series field winding being wound so that when the current fiows to the battery the field is weakened and when the current flows from the battery the field is strengthened, a cut-out in the connection between the armature and the battery, and a connection containing a starting switch shunting the cut-out. and higher resistance section of the series. field winding.

5. The combination of an engine, a storage battery, a directecurrent dynamo-electric machine connected with the engine to draw current from the storage battery as a motor to start'theengine and to be driven by the engine as a dynamo to furnish cur-, rent for charging the storagebattery, said dynamo-electric machine having an armature, a shunt field winding and a Series field winding divided into two sections, one sec.v tion beingof higher resistance thany the other, connections including a cuteout closed when the machine is running as a. dynamo and open when the machine is at rest for leading the current through the higher resistance section of the series field winding to charge the battery, and connections including a starting switch for leading the current around the cut-out and through the lower` resistance section of the series field winding for driving the machine as a motor, the series field winding being so wound as to oppose the shunt field winding when the machine is charging the battery and aid the shunt field winding when the .machine is run as a motor.

CARLTON L. KENNEDY.

Witnesses MABEL ACKnoYD, GEORGE ESTEBBINS.

Copies o( this -patent'may beobtancd for five cents each, by addressing the Commissioner o! Patenti. Washington, D. C. 

